actually, i wouldn't recommend that someone who wasn't a professional or who didn't have a good deal of experience handling dogs pin a large, unsocialized, fearful dog. <i>however</i>, pinning a dog down gently but firmly can actually work rather well in these cases<i>if you can prevent the dog from responding with stereotyped behaviors or driving you off</i>. You aren't causing pain if the restraint is properly applied, but you're preventing the dog from responding in the way that it usually would to a stimulus, which helps extinguish the response. And that's just for general freaking out. If the dog is attempting to drive you away from some resource, as one poster here mentioned about her adolescent pup, i personally think that a flip-and-pin, or grab-and-hug, or some other method that brings the dog under your immediate physical control and close contact is one of the best responses possible. (of course, i'm talking about a adolescent pup's first tentative efforts, not a dog with ingrained resource-aggressiveness. That's something different. And of course i'm not talking about play-growling during play.) it provokes a strong aversive startle from the dog without causing pain, and it teaches the dog that growling or snapping at you in such a way not only -doesn't- drive you off (which is the result that the dog was trying for,) but it results in exactly the opposite of what the dog wants. It is also, as you know, a very dominant move, which is
precisely what's needed to head this kind of thing off on its first occurrence.
(this is actually the method that i used to tame several territorial biter rats, who actually share a lot of behavioral responses with dogs, but are even harder to punish meaningfully, or use positive reinforcement on to eliminate this type of behavior. I tried. I could produce no treat that overrode the bite-from-hiding response. They kept biting me whenever i would reach into or near a den-type area or if they were undercover somewhere. So, whenever they bit me, i'd immediately grab them, flip 'em, and pin 'em, which is a natural behavior during play and dominance battles among rats -- or if i was already holding them, i'd just keep holding them and turn them on their backs and give a quick shake. The
only time i showed such behavior to them was when they either were biting or had just bitten me. All other interactions were full of positive reinforcement. About three days later they were only mouthing me, which was acceptable, and the next time i got bit by one of those rats was about a year and some later when one of them was in respiratory distress and not exactly conscious. Other than the biting, which only ever occurred in limited areas, they never showed any fear of me; in fact, they'd do just about anything to interact with me, most of the time. The point is: Delivering appropriate punishment to an animal in a way that it understands and can control isn't going to cause mental damage to the animal, and can be extremely effective and humane.)
sometimes punishment really -is- the best response: If you're trying to teach the dog not to do something that is highly rewarding to do, you have to either come up with a reward that's -better- for +r training ... Or an aversive stimulus that's stronger. And since punishment can often end a behavior after one or a few applications,
so long as the dog hasn't had time to practice and reinforce the behavior, it's often easier on you and the dog in the long run; a mild punishment could stop at the start, with one application, what it would take weeks or months of another method to try and correct -- and all that time you haven't ended the behavior, the dog is usually succeeding at reinforcing it.
Also, i would disagree with your assessment that pinning or otherwise applying similar punishments causes your dog to think that you're 'mean'. Done properly, the dog doesn't experience anything other than mild physical discomfort, which -should- end immediately when the dog submits -- and you should mark this point, the end of punishment, with a marker of some sort, you let it up, and then
reward it for complying. studies have shown that dogs don't resent punishments that are applied in the correct proportion and on a contingent basis; in fact, they seem to benefit from it, coming to understand limits and obtaining better impulse control. Of course, i don't think that this means that you should hit/beat/constantly scruff/roll/whatever your dog; i consider pinning a
dog (but not a puppy) to be a much stronger response than is usually needed for most of the offenses you encounter with a dog who's at least moderately well-adjusted. (puppies are used to being corrected this way.) i find time outs to be appropriate for most dogs for most offenses, but i think that a time out, for a puppy, is actually pretty close to the top of the aversiveness scale, much higher than scruffing or pinning them is. (they have a high tolerance for physical correction, proportionate to their size, but social isolation is an extremely stressful experience for most puppies.)
...holy dang this got long.

but the point is, different problems need different solutions, and punishment isn't, by itself, a bad thing, and mild aversive punishments can actually help improve your dog's ability to react to adversity and enhance the leader-follower bond. However, for many people, punishment can be extremely difficult to deliver properly, both because they misunderstand how to apply it, cannot judge the right intensity, cannot judge the right type of punishment for the offense, and tend to get emotionally invested in it. They apply it on a noncontingent basis so the dog doesn't know why it's getting punished and they give the dog no way to feel that it's in control of being punished or not. And most people suck at really -reading- their dogs and understanding their motivations, which is necessary for formulating proper punishments and punishment intensities. All of these things can lead to really screwed up dogs.